OdinJobs have a interesting resources for PHP developers, an US job market overview for PHP related jobs. Beside that data are available for 2008-2009 only you can have an idea about salary range of PHP related jobs in different US states. I have found many new jobs from the website search but unfortunately it’s not yet available in the market overview.
According to Odin’s PHP Salary Histogram salaries are between from $20K to $180K, while average salary range around $70K. Notice that Odin collects jobs from job boards, corporate websites, groups etc.
PHP jobs demand in US seems concentrated mainly in New York, Illinois, Texas, California, and Massachusetts, with a peak in California with 28229 jobs overall. But from a salary point of view, Idaho got the highest salaries with $100K median salary, followed by Washington, Arkansas, California, and Massachusetts.
More trends available at Odin PHP Job Market overview